Posttranslational Modifications of the Master Transcriptional Regulator NPR1 Enable Dynamic but Tight Control of Plant Immune Responses.

Published

Journal Article

NPR1, a master regulator of basal and systemic acquired resistance in plants, confers immunity through a transcriptional cascade, which includes transcription activators (e.g., TGA3) and repressors (e.g., WRKY70), leading to the massive induction of antimicrobial genes. How this single protein orchestrates genome-wide transcriptional reprogramming in response to immune stimulus remains a major question. Paradoxically, while NPR1 is essential for defense gene induction, its turnover appears to be required for this function, suggesting that NPR1 activity and degradation are dynamically regulated. Here we show that sumoylation of NPR1 by SUMO3 activates defense gene expression by switching NPR1's association with the WRKY transcription repressors to TGA transcription activators. Sumoylation also triggers NPR1 degradation, rendering the immune induction transient. SUMO modification of NPR1 is inhibited by phosphorylation at Ser55/Ser59, which keeps NPR1 stable and quiescent. Thus, posttranslational modifications enable dynamic but tight and precise control of plant immune responses.

Full Text

Duke Authors

Cited Authors

  • Saleh, A; Withers, J; Mohan, R; Marqués, J; Gu, Y; Yan, S; Zavaliev, R; Nomoto, M; Tada, Y; Dong, X

Published Date

  • August 2015

Published In

Volume / Issue

  • 18 / 2

Start / End Page

  • 169 - 182

PubMed ID

  • 26269953

Pubmed Central ID

  • 26269953

Electronic International Standard Serial Number (EISSN)

  • 1934-6069

International Standard Serial Number (ISSN)

  • 1931-3128

Digital Object Identifier (DOI)

  • 10.1016/j.chom.2015.07.005

Language

  • eng